1. Field of the Invention
The present invention relates to an automobile external wide-angle rearview mirror, which has multiple wide-angle viewing zones integrated as a continuous reflective surface so as to reduce blind spots, distortions and interferences to increase driving safety.
2. Description of Related Art
Automobile external rearview mirrors are very important for driving safety, particularly when driving on a curved road, changing lane, cornering or backing up. The automobile external rearview mirror normally requires a necessary minimum range for visual angle, less interference and distortion and blind spots for the driving safety problem.
One conventional external rearview mirror is a plane mirror as shown in FIG. 6. The advantage of the plane type rearview mirror is that the image reflected therefrom is completely a plane image without any distortion. However the plane mirror has only a narrow visual angle, which is a main drawback of the conventional plane type rearview mirror.
As shown in FIG. 7, a stick-on type arc-surface wide-angle circular mirror (70) now available on the market can be attached on the plane mirror in order to give an enlarged the visual angle of the rearview mirror. Because the stick-on type arc-surface wide-angle circular mirror (70) normally has a small curvature, it certainly has a distorted reflecting image, which always interferes with the image reflected from the plane mirror. Moreover, the stick-on type mirror (70) often falls off the plane mirror because of moisture affecting the adhesion thereof or vibration.
Another conventional automobile external rearview mirror as shown in FIG. 8 is an arc-surface wide-angle rearview mirror defined with a large curvature. Therefore it normally has a visual angle larger than that of the plane type mirror. The problem of the arc-surface wide-angle rearview mirror is the image reflected from the arc-surface mirror still has some distortions especially when driving the automobile in a turning maneuver, in which time traffic accidents are caused frequently.
To overcome the shortcomings of the conventional automobile external rearview mirror, various improved automobile external rearview mirrors are designed. For an example, as shown in FIGS. 9 and 10, an automobile external wide-angle rearview mirror is integrated with a continuous reflective arc-surface including a main zone (80), an outer side zone (81), a lower side zone (82) and a non-action zone (83), which are respectively defined with different curvatures. The non-action zone (83) is disposed between the outer side zone (81) and the lower side zone (82), and is actually an extension portion of both the outer side zone (81) and the lower side zone (82), so that the image reflected from the non-action zone (83) is distorted to a great extent.
There is still another example as shown in FIG. 11, an automobile external rearview mirror is integrated with two separate parts, i.e., left and right parts, which are respectively defined with two different curvatures. However the images from the two different parts must interfere with each other, which certainly influences visual acuity of a driver.
Therefore, it is an objective of the invention to provide an improved automobile external wide-angle rearview mirror to mitigate and/or obviate the aforementioned problems.
The main object of the present invention is to provide an automobile external wide-angle rearview mirror, which is integrated with a main zone disposed at an inner side thereof and multiple upper and lower outer side zones respectively disposed at an outer side thereof. The main zone is defined with a predetermined curvature and extended symmetrically from a horizontal central line thereof to the upper and lower edges thereof. The main zone borders upon the multiple upper and lower outer zones at two tangent lines disposed substantially symmetrical at opposite sides of the horizontal central line thereof. The multiple upper and lower outer side zones are respectively defined with curvatures gradually changed from inner sides to outer sides thereof. Whereby the integrated automobile external rearview mirror of the invention provides a continuous reflective image with little distortion and interference in a large wide-angle visual range.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.